1. Field of the Invention
The present invention relates to a rotation angle sensor using a magnetic sensitive element.
2. Description of the Related Art
A rotation angle sensor using a magnetic sensitive element is used as a rotation angle sensor that can be configured small in size and has no fear of causing contact defect due to a foreign matter, thereby suitable for detecting, for example, a depressing angle of an accelerator pedal or a rotation angle of a shaft rotatable in accordance with an operation of the shift lever for a vehicle. A conventional example of such a rotation angle sensor is disclosed, for example, in Japanese Patent Application Laid-open No. 2003-194580.
FIG. 7A is a cross-sectional view illustrating a rotation angle sensor 100 according to the conventional example of the aforementioned Patent Document, and FIG. 7B is a schematic view illustrating the positional relationship among major constituents of the rotation angle sensor 100 illustrated in FIG. 7A, seen from the axis direction of a rotating shaft 101 of the sensor 100. The rotation angle sensor 100 includes a rotating shaft 101 rotating together with a member to be detected, rotation angle of which is a detection object, a ring-shaped permanent magnet 102 fixed to the outer circumferential surface of the rotating shaft 101, yokes 103 surrounding the outer circumferential surface 102a of the permanent magnet 102 with a certain clearance D being formed between the outer circumferential surface 102a and the yokes 103, and a Hall IC 104 arranged in a gap between the yokes 103. The rotation angle sensor 100 detects a rotation angle of the member to be detected based on a change in a magnetic field, occurring due to the permanent magnet 102 when the rotating shaft 101 is rotated, detected by the Hall IC 104. In the rotation angle sensor 100, the yokes 103 are arranged in a state of being embedded in a housing 105 made of a resin material.